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Discussion Starter #1 (Edited)
Two weeks ago, I was driving home and noticed my car would start to run rough every time I stepped on the gas. It would cruise just fine, but stutter under load. I started researching the issue and came to the conclusion that it was a fuel delivery issue, but I was hoping it was just the fuel filter.

I'm crazy busy at work right now and didn't have time to troubleshoot on my own so I had the car towed to the local Euro indy. I explained the issue, but held back on my suspicions because I didn't want to influence their decision making. When I checked in the next day, they told me that my fuel trims were out of whack and they were smoke testing for vacuum leaks. They reported that one of my oil separators had a hole in it (massive) and that was most likely the problem. The next day they replaced it (by this point I was 1 hour in for diag and .5 for labor) but said there were still some vacuum leaks. Once the first one was found, they found more leaks down stream. Ok, at this point I'm in for another 2 hours of diagnostic work and 1 hour of labor. Once everything was buttoned back up, the problem persisted, although it was 'getting better'.

At this point they started checking fuel delivery and isolated the problem to the fuel pump. I asked if the filter was bad/clogged because I didn't see a record of it being replaced. They said they tested the fuel pressure prior to the fuel filter and were satisfied with the results.

By now, my bill is up to $1230. Ouch. Not a problem, it fits into the mx budget.

I get the car back and noticed it took a wee bit longer than usual to start. I figured it was probably just related to all of the work on the fuel system (maybe some air caught in the line) and it would sort itself out.

Over the next couple of days, it procedes to get worse. After the weekend, I could barely get the car to start. It would start without a problem if I tried immediately after shutting down the car. To me it sounds like the fuel lines were losing pressure when the pump wasn't on.

I took the car back to the shop. I called back today (after 24 hours) and asked for an update. They confirmed my suspicion and said the system was losing pressure and the long start up was due to the fuel pump re-pressurizing the system. He suggested that I replace the regulator and fuel pump ($131) and it would be two hours worth of labor.

He then went on to say, 'this is what probably killed your fuel pump to begin with. it had to re-pressurize the line and it over worked itself' -I'm paraphrasing.. HOLD ON. The car started just fine before I brought it into the shop, when it came out, this was a NEW problem.

We, err, debated back and forth for a minute until he finally asked 'Well, what do you want me to do about it?'

I just want the car fixed. Order the parts.

I'm trying to sell the car and I'm generating some interest, locally and out of town. I can't show the car if it's sitting in a shop. I just want the car fixed BUT I don't want to get taken to the cleaners in the process.

My questions is a two parter:

1. Does the mechanic's approach and pricing seem reasonable?

2. Is there anyway that anything done to the car during the installation of the fuel pump could have caused the long start issue that I'm currently explaining?

I'm going to research fuel system diagrams so I have a better understanding when I go to pick up the car tomorrow.

I was seeing red when the guy told me that if I knew how the whole system worked, I would understand what he was trying to tell me better.

Edit:
Cost breakdown
Diag rough running/CEL - replace oil separator
1.5 hours of labor
$40 in parts

Continued diag and replace two vacuum hoses/valves
3 hours of labor
$40 in parts

Replace fuel pump
3 hours labor
$439 for parts

Estimate for future work

Replace fuel filter/regulator
2 hours of labor
$131 for parts
 

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I'm not too good at math but $1230 for 4 hours of labor?

$131 for a fuel pump and regulator is pretty cheap, although at these labor rates cheap isn't really descriptive.

The likely cause is the fuel pump for the hesitation and/or an internal leak in the fuel line inside of the tank (for the delayed starting), more likely the pump.

I'd really like to see a picture of the hole in the oil separator.

Not all indys are angles. Good luck.





PLEASE NOTE THAT I DO NOT OWN AN M5 AND THIS POST IS NOT INTENDED TO BE ARROGANT. PLEASE READ THE IMPORTANT REVISED DISCLAIMER THAT APPLIES TO THIS POST
 

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Discussion Starter #3
I added the price breakdown. $1230 for parts and labor. I think the loss of pressure is directly related to the installation of the new fuel pump, mechanic doesn't see it the same way.
 

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The odds are pretty good that the loss of pressure is due to the installation of the fuel pump.






PLEASE NOTE THAT I DO NOT OWN AN M5 AND THIS POST IS NOT INTENDED TO BE ARROGANT. PLEASE READ THE IMPORTANT REVISED DISCLAIMER THAT APPLIES TO THIS POST
 

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Just me......... you should have posted BEFORE you took your car to a shop. Sounds a lot like a failing injector that is leaking. First the car started running rough, just like an injector not working perfect. Second now you have delayed starts, 1 no fuel pressure because injector leaked it out, 2 bunch of fuel in one cylinder IE flooded. Vacuum leak lets air in which balances that fault a bit. Mechanic fixes vacuum leak, now only the true fault is left. Car runs like crap. Standard.

It would take 3 or 4 hours to do the tests to figure this out. Give the guy more cash but ask him to work faster. You could tell him it is a leaking injector but I suspect he will blow you off, besides I am only guessing and have done no tests.Testing takes time, it seems unreasonable but it is not. You would love it to be the fuel filter, but I can tell you it is not. Totally different symptoms.
 

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Since you posted after I did........ the new fuel pump probably added the right pressure, higher and caused the injector to leak better. Don't want to give you the bad news but wait till he tells you how much to pull the injectors.
These cars are cheap to buy, NOT MAINTAIN. If you can't fix it yourself.........................................................................................Ouch!!
 

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Discussion Starter #7
Since you posted after I did........ the new fuel pump probably added the right pressure, higher and caused the injector to leak better. Don't want to give you the bad news but wait till he tells you how much to pull the injectors.
These cars are cheap to buy, NOT MAINTAIN. If you can't fix it yourself.........................................................................................Ouch!!
Thanks. If it turns out to not be the fuel filter (and I suspect it won't be) then I'm going to press him on the fuel pump issue.

I'll dig more into the fuel injector possibility, but the car seemed to run fine once it started. Also, pressure bled from the system really quickly, like within 10 minutes. Odds are, unless this guy is willing to look into the fuel pump installation, I'm going to bring the car home and troubleshoot from there. I'm not throwing anymore cash at this guy to fix the problem.

I'm assuming pulling the spark plugs would tell me a little more about condition of the injectors.
 

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Thanks. If it turns out to not be the fuel filter (and I suspect it won't be) then I'm going to press him on the fuel pump issue.

I'll dig more into the fuel injector possibility, but the car seemed to run fine once it started. Also, pressure bled from the system really quickly, like within 10 minutes. Odds are, unless this guy is willing to look into the fuel pump installation, I'm going to bring the car home and troubleshoot from there. I'm not throwing anymore cash at this guy to fix the problem.

I'm assuming pulling the spark plugs would tell me a little more about condition of the injectors.
If the car starts up fine in cold-starts but struggles to start up when the engine is already warm (hot start) this would point to the fuel lines not holding pressure. A leaky injector is probable, but not the only possibility. Since they replaced the fuel pump I would try to visually inspect it and make sure that there isn't any obvious issue with the installation.
 

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This thread highlights a truth: We pay professionals not for their labor, but their expertise and opinions. Doctor, Laywer, Mechanic...if it was just 'do this' then we could pay joe blow $25 an hour....Of course one doesnt know their level of expertise or wisdom prior to commitment, do we?

What I dont like in this whole mess is that the baseline maintenance item- fuel filter- should have simply been replaced immediately. One hour of "diagnostics" saved would cover part+install. If it didnt fix it, you still needed the maintenance.

I do think you erred in playing your cards close to the vest. Instead of entering as (perhaps) partners, you are adversaries. He might have blown you off, but if not you'd feel they were doing stuff with your approval.

Say, what CEL/codes did they get? I had a mess of misfires, seemed to be fuel, so I changed filter and pump...and then it turned otu to be ONE single bad coil causing multiple cyl misfires.... have a lightly used pump that was working when removed, only 165k miles. ;)

Finally, someone above was right: you should have taken the 45 seconds to pull Peake codes and posted here, BEFORE bringing it in.
 

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Discussion Starter #10
Update:

There was a pin hole leak in the accordion hose. I would have thought the new fuel pump came with a new hose...

As I type this I didn't think to ask the mechanic of the hose was new (and had a pinhole) or if they tried to reuse the old hose.

 

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I'm not too good at math but $1230 for 4 hours of labor?

$131 for a fuel pump and regulator is pretty cheap, although at these labor rates cheap isn't really descriptive.

The likely cause is the fuel pump for the hesitation and/or an internal leak in the fuel line inside of the tank (for the delayed starting), more likely the pump.

I'd really like to see a picture of the hole in the oil separator.

Not all indys are angles. Good luck.





PLEASE NOTE THAT I DO NOT OWN AN M5 AND THIS POST IS NOT INTENDED TO BE ARROGANT. PLEASE READ THE IMPORTANT REVISED DISCLAIMER THAT APPLIES TO THIS POST

Damn I'm good :rofl:




PLEASE NOTE THAT I DO NOT OWN AN M5 AND THIS POST IS NOT INTENDED TO BE ARROGANT. PLEASE READ THE IMPORTANT REVISED DISCLAIMER THAT APPLIES TO THIS POST
 
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